Lever mechanism for interlocking machines



Feb. '3, 1-931. i v A H. MARANDA 1,791,469

LEVER MECHANISM FOR INTERLOCKING' MACHINES Filed June '7, 1930 INVENTOR H. H. Mq Panda,

Patented Feb. 3, 1931 UNITED STATES PATENT OFFIQE ALBERT H. MARANDA, 0F SWISSVALE, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA LEVER MECHANISM FOR INTERLOCKING MACHINES Application filed June 7, 1930. Serial No. 459,698.

My invention relates to lever mechanism for interlocking machines, and has for an object the provision of novel means for in suring that an interlocking machine lever will be stopped and latched at least momentarily in a definite intermediate position during movement of the lever from one extreme position to the other.

I will describe one form of lever mechanism embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawing, Fig. 1 is a view partially isometric and partially diagrammatic showing an interlocking machine lever provided with mechanism embodying my invention, and arranged for the control of a railway signal. Fig. 2 is a sectional view on the line 11-11 of Fig. 1. Fig. 3 is an enlarged sectional view on the line IIIIII of Fig. 1.

Similar reference characters refer to similar parts in all three views.

Referring to the drawing, the reference character 1 designates a lever which may, for example, be one of a plurality of similar levers built into any of the well known forms of interlocking machines for controlling switches and signals or other trafiic governing devices from a central control point, such as an interlocking cabin. One form of interlocking machine in which the lever may be employed is shown and described in Letters Patent of the United States No. 575,908, issued to J. G. Schreuder on January 26th, 1897, for switch and signal apparatus. Slidably mounted between guides 2 and 3 formed on the lever 1 is a latch 4 which is held in place by a cap bearing 5. The upper end of the latch 4 carries a machine screw 6 which is locked in place by means of a nut 7. The free end of the machine screw 6 extends with considerable clearance through an elongated hole 8 in the lever, as best seen in Fig. 2, and has journaled thereon between its head and the lever, a thumb piece 9. An integral extension 10 on the thumb piece 9 projects into the elongated hole 8, and the lower edges of this extension cooperate with two shoulders 11 and 12 formed at the opposite sides of the hole Sin such manner that, if the thumb piece 9 is rotated through a small arc in either direction from the position in which it is illustrated in the drawing, one or the other of these edges will engage the adjacent shoulder and move the latch upwardly between the guides against the bias of-a spring 18 which returns the latch to its normal position when the thumb piece is released.

Located adjacent the path of movement of the lever 1 is a latching quadrant 14 having a curved upper surface provided with three spaced notches 15, 16 and 17. These notches are adapted to receive the latch 41, when the thumb piece is released, for locking the lever in placein predetermined positions and, as here shown, are so arranged that the lever may be locked in its middle, its extreme lefthand, or its extreme right-hand position, respectively. I I

As pointed out hereinbefore, the lever may be utilized to control traffic governing devices of any suitableform. For example, as here shown, the lever is employed to control a semaphore signal 18 of the well known type. To this end, the lever is provided with a contact finger 19 which isarranged to engage a contact segment 20 to close a contact 1920 when the lever occupies its middle position, its extreme left-hand position, or any position intermediate these two positions. The contact finger 19 is also arranged to engage acontact segment 21 to close a contact 1921 when the lever occupies its extreme left-hand position. The contact segments 20 and 21 are connected with'the operating mechanism of the signal by means of conductors 22 and 23, respectively, and the contact finger 19 is connected with the operating mechanism through a wire 24, a battery 25, and a wire 26. The operating mechanism of the signal is so constructed that when contact 19-20 is closed, the signal will move to a position in which it displays a caution indication, and when contacts 19-20 and 1921 are both closed, the signal will move moved to its middle or its extreme left-hand position.

Vith the lever mechanism constructed in the manner thus far described, it will be apparent that if the thumb piece 9 is operated to raise the latch, the lever 1 may be swung freely from one extreme position to the other, thereby permitting the signal to be moved to its proceed position by an uninterrupted movement of the lever 1. In some types of signal systems, however, and particularly in certain forms of block signal systems, whercin the signals for controlling traffic over a stretch of track are controlled entirely by the lever in the manner described, it is desirable to impose some restriction on the movement of the lever so that the oper tor must perform some auxiliary function during its operation from one extreme position to the other either for the purpose of compelling him to think before moving the lever to the position in which the signal controlled by the lever displays a clear indication, or to provide time for the electric locking of other levers in the interlocking machine, or for the performance of other similar functions. For this purpose, I provide an arc-shaped guide 27 which is secured to the top of the latching quadrant, and which is provided with alongitudinal slot 28 which extends for some distance on either side of the notch 15. A portion 29 of a stop 29 extends upwardly with considerable clearance through this slot, as best seen in Fig. 3, and is riveted or otherwise fastened to an arc-shaped member 30 located on the upper side of the guide. The stop is intended to be manually moved along the guide 27 from one end of the slot to the other, and to facilitate moving the stop along the slot, knobs 31 are secured to the member 30. The parts are so proportioned that when the latch is in the notch 15, the stop will clear the top of the latch, but that, when the latch is moved out of the notch by operation of the thumb piece 9, the stop will extend into the path of movement of the top of the latch.

The operation of the lever mechanism is as follows: When it is desired to operate the lever from the extreme position in which it is shown in the drawing to the other extreme position, the latch 4 is first moved out of engagement with the notch 17 by operating the thumb piece 9, and the lever is then moved to its central position. Vhen the lever reaches its central position, the top of the latch engages the stop 29 and prevents further movement of the lever until the stop is moved over the top of the latch to the opposite end of the slot 28 from that in which it is illustrated in the drawing. In order to move the stop over the latch, the latch must be released and allowed to enter the notch 15. When this has been done and the stop has been moved over the latch, the latch may then be withdrawn from the notch 15 and the move- Lvenese is impossible to move a lever from one extreme position to another to operate a signal or throw a switch unless the lever is stopped and latched in an intermediate position long enough to move the stop past the latch. This operation insures that an operator will not move the lever past its central position without thinking and cause a false or improper operation of the governing device controlled by the lever.

Although I have herein shown and described only one form of lever mechanism embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. The combination with an interlocking machine lever, of a latching quadrant located adjacent the path of movement of said lever and provided with a notch, a latch on said lever adapted to enter said notch for at times holding said lever in a predetermined position, means on said lever for withdrawing said latch from said notch, and a manually operable stop projecting into the path of movement of said latch when said latch is withdrawn from said notch but movable past said latch when said latch is in said notch for preventing uninterrupted movement of said lever past the position in which said latch enters said notch.

2. The combination with an interlocking machine lever, of a latching quadrant located adjacent the path of movement of said lever and provided with a notch, a latch on said lever adapted to enter said notch for at times holding said lever in a predetermined position, means on said lever for withdrawing said latch from said notch, a slotted guide associated with said latching quadrant, and a stop slidable along the slot in said guide and movable past said latch when and only when said latch is in said notch for preventing said lever from being moved past the position at which said latch enters said notch unless said stop is first moved past said latch when said latch is in said slot.

3. The combination with an interlocking machine lever, of a latch on said lever, a latching quadrant located adjacent the path of movement of said lever and provided with a plurality of notches adapted to receive said latch to lock said lever in predetermined position-s, means on said lever for at times withdrawing said latch from engagement with said notches, a guide associated with said quadrant and provided with a longitudinal slot located above an intermediate one of said notches, a stop projecting into the path of movement of said latch when said latch is withdrawn from said notch but movable along said slot past said latch when said latch is in said one intermediate notch, said stop being attached to a member located on the opposite side of said guide from said latch, and knobs on said member for facilitating movement of said stop, the parts being so proportioned that when said lever is operated said stop will engage said latch and prevent movement of said lever past said one intermediate notch unless said latch is first allowed to enter said intermediate notch and said stop is moved past said latch while said latch 00- cupies said intermediate notch.

In testimony whereof I alfix my signature.

ALBERT H. MARANDA. 

